xref: /llvm-project/lldb/source/Utility/StringExtractorGDBRemote.cpp (revision bc04d240850bab340341eaf3601c5ca996667319)
1 //===-- StringExtractorGDBRemote.cpp --------------------------------------===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 
9 #include "lldb/Utility/StringExtractorGDBRemote.h"
10 
11 #include <cctype>
12 #include <cstring>
13 
14 constexpr lldb::pid_t StringExtractorGDBRemote::AllProcesses;
15 constexpr lldb::tid_t StringExtractorGDBRemote::AllThreads;
16 
17 StringExtractorGDBRemote::ResponseType
18 StringExtractorGDBRemote::GetResponseType() const {
19   if (m_packet.empty())
20     return eUnsupported;
21 
22   switch (m_packet[0]) {
23   case 'E':
24     if (isxdigit(m_packet[1]) && isxdigit(m_packet[2])) {
25       if (m_packet.size() == 3)
26         return eError;
27       llvm::StringRef packet_ref(m_packet);
28       if (packet_ref[3] == ';') {
29         auto err_string = packet_ref.substr(4);
30         for (auto e : err_string)
31           if (!isxdigit(e))
32             return eResponse;
33         return eError;
34       }
35     }
36     break;
37 
38   case 'O':
39     if (m_packet.size() == 2 && m_packet[1] == 'K')
40       return eOK;
41     break;
42 
43   case '+':
44     if (m_packet.size() == 1)
45       return eAck;
46     break;
47 
48   case '-':
49     if (m_packet.size() == 1)
50       return eNack;
51     break;
52   }
53   return eResponse;
54 }
55 
56 StringExtractorGDBRemote::ServerPacketType
57 StringExtractorGDBRemote::GetServerPacketType() const {
58 #define PACKET_MATCHES(s)                                                      \
59   ((packet_size == (sizeof(s) - 1)) && (strcmp((packet_cstr), (s)) == 0))
60 #define PACKET_STARTS_WITH(s)                                                  \
61   ((packet_size >= (sizeof(s) - 1)) &&                                         \
62    ::strncmp(packet_cstr, s, (sizeof(s) - 1)) == 0)
63 
64   // Empty is not a supported packet...
65   if (m_packet.empty())
66     return eServerPacketType_invalid;
67 
68   const size_t packet_size = m_packet.size();
69   const char *packet_cstr = m_packet.c_str();
70   switch (m_packet[0]) {
71 
72   case '%':
73     return eServerPacketType_notify;
74 
75   case '\x03':
76     if (packet_size == 1)
77       return eServerPacketType_interrupt;
78     break;
79 
80   case '-':
81     if (packet_size == 1)
82       return eServerPacketType_nack;
83     break;
84 
85   case '+':
86     if (packet_size == 1)
87       return eServerPacketType_ack;
88     break;
89 
90   case 'A':
91     return eServerPacketType_A;
92 
93   case 'Q':
94 
95     switch (packet_cstr[1]) {
96     case 'E':
97       if (PACKET_STARTS_WITH("QEnvironment:"))
98         return eServerPacketType_QEnvironment;
99       if (PACKET_STARTS_WITH("QEnvironmentHexEncoded:"))
100         return eServerPacketType_QEnvironmentHexEncoded;
101       if (PACKET_STARTS_WITH("QEnableErrorStrings"))
102         return eServerPacketType_QEnableErrorStrings;
103       break;
104 
105     case 'P':
106       if (PACKET_STARTS_WITH("QPassSignals:"))
107         return eServerPacketType_QPassSignals;
108       break;
109 
110     case 'S':
111       if (PACKET_MATCHES("QStartNoAckMode"))
112         return eServerPacketType_QStartNoAckMode;
113       if (PACKET_STARTS_WITH("QSaveRegisterState"))
114         return eServerPacketType_QSaveRegisterState;
115       if (PACKET_STARTS_WITH("QSetDisableASLR:"))
116         return eServerPacketType_QSetDisableASLR;
117       if (PACKET_STARTS_WITH("QSetDetachOnError:"))
118         return eServerPacketType_QSetDetachOnError;
119       if (PACKET_STARTS_WITH("QSetSTDIN:"))
120         return eServerPacketType_QSetSTDIN;
121       if (PACKET_STARTS_WITH("QSetSTDOUT:"))
122         return eServerPacketType_QSetSTDOUT;
123       if (PACKET_STARTS_WITH("QSetSTDERR:"))
124         return eServerPacketType_QSetSTDERR;
125       if (PACKET_STARTS_WITH("QSetWorkingDir:"))
126         return eServerPacketType_QSetWorkingDir;
127       if (PACKET_STARTS_WITH("QSetLogging:"))
128         return eServerPacketType_QSetLogging;
129       if (PACKET_STARTS_WITH("QSetIgnoredExceptions"))
130         return eServerPacketType_QSetIgnoredExceptions;
131       if (PACKET_STARTS_WITH("QSetMaxPacketSize:"))
132         return eServerPacketType_QSetMaxPacketSize;
133       if (PACKET_STARTS_WITH("QSetMaxPayloadSize:"))
134         return eServerPacketType_QSetMaxPayloadSize;
135       if (PACKET_STARTS_WITH("QSetEnableAsyncProfiling;"))
136         return eServerPacketType_QSetEnableAsyncProfiling;
137       if (PACKET_STARTS_WITH("QSyncThreadState:"))
138         return eServerPacketType_QSyncThreadState;
139       break;
140 
141     case 'L':
142       if (PACKET_STARTS_WITH("QLaunchArch:"))
143         return eServerPacketType_QLaunchArch;
144       if (PACKET_MATCHES("QListThreadsInStopReply"))
145         return eServerPacketType_QListThreadsInStopReply;
146       break;
147 
148     case 'M':
149       if (PACKET_STARTS_WITH("QMemTags"))
150         return eServerPacketType_QMemTags;
151       break;
152 
153     case 'N':
154       if (PACKET_STARTS_WITH("QNonStop:"))
155         return eServerPacketType_QNonStop;
156       break;
157 
158     case 'R':
159       if (PACKET_STARTS_WITH("QRestoreRegisterState:"))
160         return eServerPacketType_QRestoreRegisterState;
161       break;
162 
163     case 'T':
164       if (PACKET_MATCHES("QThreadSuffixSupported"))
165         return eServerPacketType_QThreadSuffixSupported;
166       break;
167     }
168     break;
169 
170   case 'q':
171     switch (packet_cstr[1]) {
172     case 's':
173       if (PACKET_MATCHES("qsProcessInfo"))
174         return eServerPacketType_qsProcessInfo;
175       if (PACKET_MATCHES("qsThreadInfo"))
176         return eServerPacketType_qsThreadInfo;
177       break;
178 
179     case 'f':
180       if (PACKET_STARTS_WITH("qfProcessInfo"))
181         return eServerPacketType_qfProcessInfo;
182       if (PACKET_STARTS_WITH("qfThreadInfo"))
183         return eServerPacketType_qfThreadInfo;
184       break;
185 
186     case 'C':
187       if (packet_size == 2)
188         return eServerPacketType_qC;
189       break;
190 
191     case 'E':
192       if (PACKET_STARTS_WITH("qEcho:"))
193         return eServerPacketType_qEcho;
194       break;
195 
196     case 'F':
197       if (PACKET_STARTS_WITH("qFileLoadAddress:"))
198         return eServerPacketType_qFileLoadAddress;
199       break;
200 
201     case 'G':
202       if (PACKET_STARTS_WITH("qGroupName:"))
203         return eServerPacketType_qGroupName;
204       if (PACKET_MATCHES("qGetWorkingDir"))
205         return eServerPacketType_qGetWorkingDir;
206       if (PACKET_MATCHES("qGetPid"))
207         return eServerPacketType_qGetPid;
208       if (PACKET_STARTS_WITH("qGetProfileData;"))
209         return eServerPacketType_qGetProfileData;
210       if (PACKET_MATCHES("qGDBServerVersion"))
211         return eServerPacketType_qGDBServerVersion;
212       break;
213 
214     case 'H':
215       if (PACKET_MATCHES("qHostInfo"))
216         return eServerPacketType_qHostInfo;
217       break;
218 
219     case 'K':
220       if (PACKET_STARTS_WITH("qKillSpawnedProcess"))
221         return eServerPacketType_qKillSpawnedProcess;
222       break;
223 
224     case 'L':
225       if (PACKET_STARTS_WITH("qLaunchGDBServer"))
226         return eServerPacketType_qLaunchGDBServer;
227       if (PACKET_MATCHES("qLaunchSuccess"))
228         return eServerPacketType_qLaunchSuccess;
229       break;
230 
231     case 'M':
232       if (PACKET_STARTS_WITH("qMemoryRegionInfo:"))
233         return eServerPacketType_qMemoryRegionInfo;
234       if (PACKET_MATCHES("qMemoryRegionInfo"))
235         return eServerPacketType_qMemoryRegionInfoSupported;
236       if (PACKET_STARTS_WITH("qModuleInfo:"))
237         return eServerPacketType_qModuleInfo;
238       if (PACKET_STARTS_WITH("qMemTags:"))
239         return eServerPacketType_qMemTags;
240       break;
241 
242     case 'P':
243       if (PACKET_STARTS_WITH("qProcessInfoPID:"))
244         return eServerPacketType_qProcessInfoPID;
245       if (PACKET_STARTS_WITH("qPlatform_shell:"))
246         return eServerPacketType_qPlatform_shell;
247       if (PACKET_STARTS_WITH("qPlatform_mkdir:"))
248         return eServerPacketType_qPlatform_mkdir;
249       if (PACKET_STARTS_WITH("qPlatform_chmod:"))
250         return eServerPacketType_qPlatform_chmod;
251       if (PACKET_MATCHES("qProcessInfo"))
252         return eServerPacketType_qProcessInfo;
253       if (PACKET_STARTS_WITH("qPathComplete:"))
254         return eServerPacketType_qPathComplete;
255       break;
256 
257     case 'Q':
258       if (PACKET_MATCHES("qQueryGDBServer"))
259         return eServerPacketType_qQueryGDBServer;
260       break;
261 
262     case 'R':
263       if (PACKET_STARTS_WITH("qRcmd,"))
264         return eServerPacketType_qRcmd;
265       if (PACKET_STARTS_WITH("qRegisterInfo"))
266         return eServerPacketType_qRegisterInfo;
267       break;
268 
269     case 'S':
270       if (PACKET_STARTS_WITH("qSaveCore"))
271         return eServerPacketType_qLLDBSaveCore;
272       if (PACKET_STARTS_WITH("qSpeedTest:"))
273         return eServerPacketType_qSpeedTest;
274       if (PACKET_MATCHES("qShlibInfoAddr"))
275         return eServerPacketType_qShlibInfoAddr;
276       if (PACKET_MATCHES("qStepPacketSupported"))
277         return eServerPacketType_qStepPacketSupported;
278       if (PACKET_STARTS_WITH("qSupported"))
279         return eServerPacketType_qSupported;
280       if (PACKET_MATCHES("qSyncThreadStateSupported"))
281         return eServerPacketType_qSyncThreadStateSupported;
282       break;
283 
284     case 'T':
285       if (PACKET_STARTS_WITH("qThreadExtraInfo,"))
286         return eServerPacketType_qThreadExtraInfo;
287       if (PACKET_STARTS_WITH("qThreadStopInfo"))
288         return eServerPacketType_qThreadStopInfo;
289       break;
290 
291     case 'U':
292       if (PACKET_STARTS_WITH("qUserName:"))
293         return eServerPacketType_qUserName;
294       break;
295 
296     case 'V':
297       if (PACKET_MATCHES("qVAttachOrWaitSupported"))
298         return eServerPacketType_qVAttachOrWaitSupported;
299       break;
300 
301     case 'W':
302       if (PACKET_STARTS_WITH("qWatchpointSupportInfo:"))
303         return eServerPacketType_qWatchpointSupportInfo;
304       if (PACKET_MATCHES("qWatchpointSupportInfo"))
305         return eServerPacketType_qWatchpointSupportInfoSupported;
306       break;
307 
308     case 'X':
309       if (PACKET_STARTS_WITH("qXfer:"))
310         return eServerPacketType_qXfer;
311       break;
312     }
313     break;
314 
315   case 'j':
316     if (PACKET_STARTS_WITH("jModulesInfo:"))
317       return eServerPacketType_jModulesInfo;
318     if (PACKET_MATCHES("jSignalsInfo"))
319       return eServerPacketType_jSignalsInfo;
320     if (PACKET_MATCHES("jThreadsInfo"))
321       return eServerPacketType_jThreadsInfo;
322 
323     if (PACKET_MATCHES("jLLDBTraceSupported"))
324       return eServerPacketType_jLLDBTraceSupported;
325     if (PACKET_STARTS_WITH("jLLDBTraceStop:"))
326       return eServerPacketType_jLLDBTraceStop;
327     if (PACKET_STARTS_WITH("jLLDBTraceStart:"))
328       return eServerPacketType_jLLDBTraceStart;
329     if (PACKET_STARTS_WITH("jLLDBTraceGetState:"))
330       return eServerPacketType_jLLDBTraceGetState;
331     if (PACKET_STARTS_WITH("jLLDBTraceGetBinaryData:"))
332       return eServerPacketType_jLLDBTraceGetBinaryData;
333     break;
334 
335   case 'v':
336     if (PACKET_STARTS_WITH("vFile:")) {
337       if (PACKET_STARTS_WITH("vFile:open:"))
338         return eServerPacketType_vFile_open;
339       else if (PACKET_STARTS_WITH("vFile:close:"))
340         return eServerPacketType_vFile_close;
341       else if (PACKET_STARTS_WITH("vFile:pread"))
342         return eServerPacketType_vFile_pread;
343       else if (PACKET_STARTS_WITH("vFile:pwrite"))
344         return eServerPacketType_vFile_pwrite;
345       else if (PACKET_STARTS_WITH("vFile:size"))
346         return eServerPacketType_vFile_size;
347       else if (PACKET_STARTS_WITH("vFile:exists"))
348         return eServerPacketType_vFile_exists;
349       else if (PACKET_STARTS_WITH("vFile:fstat"))
350         return eServerPacketType_vFile_fstat;
351       else if (PACKET_STARTS_WITH("vFile:stat"))
352         return eServerPacketType_vFile_stat;
353       else if (PACKET_STARTS_WITH("vFile:mode"))
354         return eServerPacketType_vFile_mode;
355       else if (PACKET_STARTS_WITH("vFile:MD5"))
356         return eServerPacketType_vFile_md5;
357       else if (PACKET_STARTS_WITH("vFile:symlink"))
358         return eServerPacketType_vFile_symlink;
359       else if (PACKET_STARTS_WITH("vFile:unlink"))
360         return eServerPacketType_vFile_unlink;
361 
362     } else {
363       if (PACKET_STARTS_WITH("vAttach;"))
364         return eServerPacketType_vAttach;
365       if (PACKET_STARTS_WITH("vAttachWait;"))
366         return eServerPacketType_vAttachWait;
367       if (PACKET_STARTS_WITH("vAttachOrWait;"))
368         return eServerPacketType_vAttachOrWait;
369       if (PACKET_STARTS_WITH("vAttachName;"))
370         return eServerPacketType_vAttachName;
371       if (PACKET_STARTS_WITH("vCont;"))
372         return eServerPacketType_vCont;
373       if (PACKET_MATCHES("vCont?"))
374         return eServerPacketType_vCont_actions;
375       if (PACKET_STARTS_WITH("vRun;"))
376         return eServerPacketType_vRun;
377       if (PACKET_MATCHES("vStopped"))
378         return eServerPacketType_vStopped;
379       if (PACKET_MATCHES("vCtrlC"))
380         return eServerPacketType_vCtrlC;
381       break;
382 
383     }
384     break;
385   case '_':
386     switch (packet_cstr[1]) {
387     case 'M':
388       return eServerPacketType__M;
389 
390     case 'm':
391       return eServerPacketType__m;
392     }
393     break;
394 
395   case '?':
396     if (packet_size == 1)
397       return eServerPacketType_stop_reason;
398     break;
399 
400   case 'c':
401     return eServerPacketType_c;
402 
403   case 'C':
404     return eServerPacketType_C;
405 
406   case 'D':
407     return eServerPacketType_D;
408 
409   case 'g':
410     return eServerPacketType_g;
411 
412   case 'G':
413     return eServerPacketType_G;
414 
415   case 'H':
416     return eServerPacketType_H;
417 
418   case 'I':
419     return eServerPacketType_I;
420 
421   case 'k':
422     if (packet_size == 1)
423       return eServerPacketType_k;
424     break;
425 
426   case 'm':
427     return eServerPacketType_m;
428 
429   case 'M':
430     return eServerPacketType_M;
431 
432   case 'p':
433     return eServerPacketType_p;
434 
435   case 'P':
436     return eServerPacketType_P;
437 
438   case 's':
439     if (packet_size == 1)
440       return eServerPacketType_s;
441     break;
442 
443   case 'S':
444     return eServerPacketType_S;
445 
446   case 'x':
447     return eServerPacketType_x;
448 
449   case 'X':
450     return eServerPacketType_X;
451 
452   case 'T':
453     return eServerPacketType_T;
454 
455   case 'z':
456     if (packet_cstr[1] >= '0' && packet_cstr[1] <= '4')
457       return eServerPacketType_z;
458     break;
459 
460   case 'Z':
461     if (packet_cstr[1] >= '0' && packet_cstr[1] <= '4')
462       return eServerPacketType_Z;
463     break;
464   }
465   return eServerPacketType_unimplemented;
466 }
467 
468 bool StringExtractorGDBRemote::IsOKResponse() const {
469   return GetResponseType() == eOK;
470 }
471 
472 bool StringExtractorGDBRemote::IsUnsupportedResponse() const {
473   return GetResponseType() == eUnsupported;
474 }
475 
476 bool StringExtractorGDBRemote::IsNormalResponse() const {
477   return GetResponseType() == eResponse;
478 }
479 
480 bool StringExtractorGDBRemote::IsErrorResponse() const {
481   return GetResponseType() == eError && isxdigit(m_packet[1]) &&
482          isxdigit(m_packet[2]);
483 }
484 
485 uint8_t StringExtractorGDBRemote::GetError() {
486   if (GetResponseType() == eError) {
487     SetFilePos(1);
488     return GetHexU8(255);
489   }
490   return 0;
491 }
492 
493 lldb_private::Status StringExtractorGDBRemote::GetStatus() {
494   lldb_private::Status error;
495   if (GetResponseType() == eError) {
496     SetFilePos(1);
497     uint8_t errc = GetHexU8(255);
498     error.SetError(errc, lldb::eErrorTypeGeneric);
499 
500     error.SetErrorStringWithFormat("Error %u", errc);
501     std::string error_messg;
502     if (GetChar() == ';') {
503       GetHexByteString(error_messg);
504       error.SetErrorString(error_messg);
505     }
506   }
507   return error;
508 }
509 
510 size_t StringExtractorGDBRemote::GetEscapedBinaryData(std::string &str) {
511   // Just get the data bytes in the string as
512   // GDBRemoteCommunication::CheckForPacket() already removes any 0x7d escaped
513   // characters. If any 0x7d characters are left in the packet, then they are
514   // supposed to be there...
515   str.clear();
516   const size_t bytes_left = GetBytesLeft();
517   if (bytes_left > 0) {
518     str.assign(m_packet, m_index, bytes_left);
519     m_index += bytes_left;
520   }
521   return str.size();
522 }
523 
524 static bool
525 OKErrorNotSupportedResponseValidator(void *,
526                                      const StringExtractorGDBRemote &response) {
527   switch (response.GetResponseType()) {
528   case StringExtractorGDBRemote::eOK:
529   case StringExtractorGDBRemote::eError:
530   case StringExtractorGDBRemote::eUnsupported:
531     return true;
532 
533   case StringExtractorGDBRemote::eAck:
534   case StringExtractorGDBRemote::eNack:
535   case StringExtractorGDBRemote::eResponse:
536     break;
537   }
538   return false;
539 }
540 
541 static bool JSONResponseValidator(void *,
542                                   const StringExtractorGDBRemote &response) {
543   switch (response.GetResponseType()) {
544   case StringExtractorGDBRemote::eUnsupported:
545   case StringExtractorGDBRemote::eError:
546     return true; // Accept unsupported or EXX as valid responses
547 
548   case StringExtractorGDBRemote::eOK:
549   case StringExtractorGDBRemote::eAck:
550   case StringExtractorGDBRemote::eNack:
551     break;
552 
553   case StringExtractorGDBRemote::eResponse:
554     // JSON that is returned in from JSON query packets is currently always
555     // either a dictionary which starts with a '{', or an array which starts
556     // with a '['. This is a quick validator to just make sure the response
557     // could be valid JSON without having to validate all of the
558     // JSON content.
559     switch (response.GetStringRef()[0]) {
560     case '{':
561       return true;
562     case '[':
563       return true;
564     default:
565       break;
566     }
567     break;
568   }
569   return false;
570 }
571 
572 static bool
573 ASCIIHexBytesResponseValidator(void *,
574                                const StringExtractorGDBRemote &response) {
575   switch (response.GetResponseType()) {
576   case StringExtractorGDBRemote::eUnsupported:
577   case StringExtractorGDBRemote::eError:
578     return true; // Accept unsupported or EXX as valid responses
579 
580   case StringExtractorGDBRemote::eOK:
581   case StringExtractorGDBRemote::eAck:
582   case StringExtractorGDBRemote::eNack:
583     break;
584 
585   case StringExtractorGDBRemote::eResponse: {
586     uint32_t valid_count = 0;
587     for (const char ch : response.GetStringRef()) {
588       if (!isxdigit(ch)) {
589         return false;
590       }
591       if (++valid_count >= 16)
592         break; // Don't validate all the characters in case the packet is very
593                // large
594     }
595     return true;
596   } break;
597   }
598   return false;
599 }
600 
601 void StringExtractorGDBRemote::CopyResponseValidator(
602     const StringExtractorGDBRemote &rhs) {
603   m_validator = rhs.m_validator;
604   m_validator_baton = rhs.m_validator_baton;
605 }
606 
607 void StringExtractorGDBRemote::SetResponseValidator(
608     ResponseValidatorCallback callback, void *baton) {
609   m_validator = callback;
610   m_validator_baton = baton;
611 }
612 
613 void StringExtractorGDBRemote::SetResponseValidatorToOKErrorNotSupported() {
614   m_validator = OKErrorNotSupportedResponseValidator;
615   m_validator_baton = nullptr;
616 }
617 
618 void StringExtractorGDBRemote::SetResponseValidatorToASCIIHexBytes() {
619   m_validator = ASCIIHexBytesResponseValidator;
620   m_validator_baton = nullptr;
621 }
622 
623 void StringExtractorGDBRemote::SetResponseValidatorToJSON() {
624   m_validator = JSONResponseValidator;
625   m_validator_baton = nullptr;
626 }
627 
628 bool StringExtractorGDBRemote::ValidateResponse() const {
629   // If we have a validator callback, try to validate the callback
630   if (m_validator)
631     return m_validator(m_validator_baton, *this);
632   else
633     return true; // No validator, so response is valid
634 }
635 
636 llvm::Optional<std::pair<lldb::pid_t, lldb::tid_t>>
637 StringExtractorGDBRemote::GetPidTid(lldb::pid_t default_pid) {
638   llvm::StringRef view = llvm::StringRef(m_packet).substr(m_index);
639   size_t initial_length = view.size();
640   lldb::pid_t pid = default_pid;
641   lldb::tid_t tid;
642 
643   if (view.consume_front("p")) {
644     // process identifier
645     if (view.consume_front("-1")) {
646       // -1 is a special case
647       pid = AllProcesses;
648     } else if (view.consumeInteger(16, pid) || pid == 0) {
649       // not a valid hex integer OR unsupported pid 0
650       m_index = UINT64_MAX;
651       return llvm::None;
652     }
653 
654     // "." must follow if we expect TID too; otherwise, we assume -1
655     if (!view.consume_front(".")) {
656       // update m_index
657       m_index += initial_length - view.size();
658 
659       return {{pid, AllThreads}};
660     }
661   }
662 
663   // thread identifier
664   if (view.consume_front("-1")) {
665     // -1 is a special case
666     tid = AllThreads;
667   } else if (view.consumeInteger(16, tid) || tid == 0 || pid == AllProcesses) {
668     // not a valid hex integer OR tid 0 OR pid -1 + a specific tid
669     m_index = UINT64_MAX;
670     return llvm::None;
671   }
672 
673   // update m_index
674   m_index += initial_length - view.size();
675 
676   return {{pid, tid}};
677 }
678